JEE Main 2024 Physics question
A small liquid drop of radius R is divided into 27 identical liquid drops. If the surface tension is T, then the work done in the process will be :
Answer: (B)
Solution
Volume conservation: 27 × (4/3)πr³ = (4/3)πR³, so r = R/3. Work = T × ΔA = T[27 × 4π(R/3)² − 4πR²] = T(12πR² − 4πR²) = 8πR²T.